Well, it depends. If you experience glitches like some have reported to (game-breaking, worlds not loading), of course it will not get 10/10. But no game is perfect, either.
10/10 scores are (in my opinion) for games that have so many good sides that you do not think of the bad sides while playing. The Last of Us was such game, for me. GTA IV/SA got perfect scores on places too, yet they have a lot of glitches - but you didn't complain about them because GTA is pretty much for fun roaming around.
Uncharted 2 got perfect scores all around, and it has glitches. What I am getting at is that no game is perfect, but TLoU gets quite close, even with the glitches/gameplay problems. If you come and say it doesn't deserve 10/10 for other reasons, I guess you just don't like the genre.